Semiconductor memory devices and methods of arranging memory cell arrays thereof
Semiconductor memory devices with a memory cell array including a first word line and a second word line arranged in a first direction, a source line arranged in the first direction between the first word line and the second word line, a bit line pair including a first bit line and a second bit line arranged in a second direction perpendicular to the first direction, a first memory cell including a gate connected to the first word line and first and second regions respectively connected to the second bit line and the source line, and arranged in a third direction between the first direction and the second direction, and a second memory cell including a gate connected to the second word line, a third region and the second region respectively connected to the first bit line and the source line, and arranged in the third direction.
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This application claims the benefit of Korean Patent Application No. 10-2008-0048179, filed May 23, 2008, the contents of which are hereby incorporated herein by reference in their entirety.
BACKGROUND1. Field
Example embodiments relate to a semiconductor memory device, and more particularly, to a semiconductor memory device having a memory cell without a capacitor, and a method of arranging a memory cell array thereof.
2. Description of Related Art
In general, a memory cell of a dynamic semiconductor memory device includes one cell capacitor and one access transistor. Efforts have been made to increase capacity of semiconductor memory devices without increasing layout area, for example, by using dynamic memory cells having a floating body transistor without a capacitor. As a result, it is possible to fabricate improved integration density memory cells compared to conventional dynamic semiconductor memory devices. However, depending on the charge storage mechanism used (e.g., impact ionization), a device with a shared source/drain line connection (e.g., bit line) may be disturbed by an operation of another device sharing the source/drain.
SUMMARYExample embodiments may provide a semiconductor memory device, the semiconductor memory device having zero or reduced disturbances generated between adjacent memory cells, improved integration density, and which may employ a sub-word line structure. Example embodiments may also provide a method of arranging a memory cell array of a semiconductor memory device capable of achieving the above advantages.
According to an example embodiment, a semiconductor memory device includes a memory cell array including: a word line pair including a first word line and a second word line; a source line; a bit line pair including a first bit line and a second bit line; a first memory cell oblique to the first and second word lines, including a gate and first and second regions, the gate connected to the first word line, and the first and second regions respectively connected to the second bit line and the source line; a second memory cell oblique to the first and second word lines, including a gate, a third region, and the second region, the gate connected to the second word line, and the third region connected to the first bit line.
The first region of the first memory cell may overlap the second bit line, and the third region of the second memory cell may overlap the first bit line. The first word line and the second word line of the word line pair may be electrically connected to each other.
The first memory cell may include a floating body transistor in which the first region is a drain region and the second region is a source region, and the second memory cell may include a floating body transistor in which the third region is a drain region and the second region is a source region.
The first memory cell may include a first access transistor in which the second region is a source region and a gate is connected to the first word line, and a first variable resistor is connected between a drain of the first access transistor and the first region, and the second memory cell may include a second access transistor in which the second region is a source region and a gate is connected to the second word line, and a second variable resistor connected between a drain of the second access transistor and the third region.
The first memory cell may include a first selection transistor in which the second region is a source region and a gate is connected to the first word line, and a first memory transistor is connected between a drain of the first selection transistor and the first region, and the second memory cell may include a second selection transistor in which the second region is a source region and a gate is connected to the second word line, and a second memory transistor is connected between a drain of the second selection transistor and the third region. The first and second memory transistors may include a Silicon-Oxide-Nitride-Oxide-Silicon (SONOS) cell.
The semiconductor memory device may further include a row controller configured to control the word line pair and the source lines, and a column controller configured to control the bit line pair, wherein the memory cell array may further include a sensing block including a current sense amplifier that amplifies current flowing through the first bit line and the second bit line during a read operation, or a voltage sense amplifier that amplifies voltages of the first and second bit lines.
The semiconductor memory device may further include a main word line and a main source line, wherein the main word line and the main source line are respectively connected to the word line pair and the source line.
The semiconductor memory device may further include a main word line, a main source line and a plurality of word line selection signal lines, wherein the memory cell array includes: a plurality of sub-memory cell array blocks that include the first memory cell and the second memory cell; a plurality of word line selection signal drivers connected to the corresponding word line selection signal lines; a sub-word line driver connected to an output signal line of the corresponding one of the plurality of word line selection signal drivers and the main word line, and configured to drive the word line pair; and a sub-source line driver connected to an output signal line of the corresponding one of the plurality of word line selection signal drivers and the main source line, and configured to drive the source line. The sub-word line driver and the sub-source line driver may be alternately arranged with respect to each of the plurality of sub-memory cell array blocks.
According to an example embodiment, a method of arranging a memory cell array of a semiconductor memory device includes: arranging a word line pair including a first line and a second word line in a first direction; arranging a source line in the first direction between the first and second word lines; arranging a bit line pair including a first bit line and a second bit line in a second direction perpendicular to the first direction; arranging a first memory cell including a gate connected to the first word line, and a first region and a second region respectively connected to the second bit line and the source line in a third direction between the first direction and the second direction; arranging a second memory cell including a gate connected to the second word line, and a third region and the second region respectively connected to the first bit line and the source line in the third direction; and electrically connecting the first word line to the second word line.
The first region of the first memory cell may be arranged to overlap the second bit line, and the third region of the second memory cell may be arranged to overlap the first bit line. The method may further include arranging a main word line and a main source line in the first direction, wherein the main word line and the main source line are respectively connected to the word line pair and the source line.
The method may further include arranging a main word line, a main source line and a plurality of word line selection signal lines in the first direction; arranging a plurality of sub-memory cell array blocks including the first memory cell and the second memory cell and the plurality of word line selection signal drivers connected to the corresponding word line selection signal lines in the memory cell array; and alternately arranging a sub-word line driver connected to an output signal line of the corresponding one of the plurality of word line selection signal drivers and the main word line, and configured to drive the word line pair, and a sub-source line driver connected to an output signal line of the corresponding one of the plurality of word line selection signal drivers and the main source line, and configured to drive the source line, with respect to each of the plurality of sub-memory cell array blocks.
Example embodiments will be more clearly understood from the following brief description taken in conjunction with the accompanying drawings.
It should be noted that these Figures are intended to illustrate the general characteristics of methods, structure and/or materials utilized in certain example embodiments and to supplement the written description provided below. These drawings are not, however, to scale and may not precisely reflect the precise structural or performance characteristics of any given embodiment, and should not be interpreted as defining or limiting the range of values or properties encompassed by example embodiments. For example, the relative thicknesses and positioning of molecules, layers, regions and/or structural elements may be reduced or exaggerated for clarity. The use of similar or identical reference numbers in the various drawings is intended to indicate the presence of a similar or identical element or feature.
DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTSExample embodiments will now be described more fully with reference to the accompanying drawings, in which example embodiments are shown. Example embodiments may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of example embodiments to those of ordinary skill in the art. In the drawings, the thicknesses of layers and regions are exaggerated for clarity. Like reference numerals in the drawings denote like elements, and thus their description will be omitted.
It will be understood that when an element is referred to as being “connected” or “coupled” to another element, it can be directly connected or coupled to the other element or intervening elements may be present. In contrast, when an element is referred to as being “directly connected” or “directly coupled” to another element, there are no intervening elements present. Like numbers indicate like elements throughout. As used herein the term “and/or” includes any and all combinations of one or more of the associated listed items.
It will be understood that, although the terms “first”, “second”, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of example embodiments.
Spatially relative terms, such as “beneath,” “below,” “lower,” “above,” “upper” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the exemplary term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a,” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
Example embodiments are described herein with reference to cross-sectional illustrations that are schematic illustrations of idealized embodiments (and intermediate structures) of example embodiments. As such, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, example embodiments should not be construed as limited to the particular shapes of regions illustrated herein but are to include deviations in shapes that result, for example, from manufacturing. For example, an implanted region illustrated as a rectangle may have rounded or curved features and/or a gradient of implant concentration at its edges rather than a binary change from implanted to non-implanted region. Likewise, a buried region formed by implantation may result in some implantation in the region between the buried region and the surface through which the implantation takes place. Thus, the regions illustrated in the figures are schematic in nature and their shapes are not intended to illustrate the actual shape of a region of a device and are not intended to limit the scope of example embodiments.
Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which example embodiments belong. It will be further understood that terms, such as those defined in commonly-used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
The semiconductor memory device and a method of arranging a memory cell array thereof will now be described with reference to
The first memory cells MC11 and MC21 may be connected to the first word lines WL11 and WL21, the second bit line BL12, and the source lines SL1 and SL2. The second memory cells MC12 and MC22 each may be connected to the second word lines WL12 and WL22, the first bit line BL11, and the source lines SL1 and SL2. The first memory cells MC11 and MC21 may be arranged in a diagonal direction between the source lines SL1 and SL2 and the second bit line BL12. The second memory cells MC12 and MC22 may be arranged in a diagonal direction between the source lines SL1 and SL2 and the first bit line BL11.
A region connected to the second bit line BL12 of each of the first memory cells MC11 and MC21 may be formed to overlap the second bit line BL12. A region connected to the first bit line BL11 of each of the second memory cells MC12 and MC22 may be formed to overlap the first bit line BL11. A region connected to the source line SL1 of the first and second memory cells MC11 and MC12 may be shared and may overlap the source line SL1. Therefore, a region connected to the bit line of the second memory cell MC12 may be separated from a region connected to the bit line of the first memory cell MC21.
The first and second word lines (WL11 and WL12), (WL21 and WL22), and (WL31 and WL32) may be configured for simultaneous activation. Although not shown in the drawing, the first and second word lines may be controlled by a row controller (not shown). The row controller may simultaneously activate the first and second word lines (WL11 and WL12), (WL21 and WL22), and (WL31 and WL32). Alternatively, the first word lines WL11, WL21, and WL31 may be electrically connected to the second word lines WL12, WL22, and WL32, respectively, so that the connected word lines may be controlled by the row controller (not shown).
For purposes of explanation, in the semiconductor memory device illustrated in
The integration density of the semiconductor memory device may be improved or increased by disposing the memory cells MC11, MC12, MC21 and MC22 in a diagonal direction. If the first and second word lines (WL11 and WL12) and (WL21 and WL22) connected to the first and second memory cells (MC11 and MC12) and (MC21 and MC22), respectively, are electrically connected, the number of word lines driven by the row controller (not shown) may be reduced. Therefore, the row controller (not shown) may be simplified because a sub-word line structure (e.g., hierarchical word line structure) may be employed.
In
A semiconductor memory device according to an example embodiment will now be described with reference to
Methods of operating memory blocks according to example embodiments will now be described with reference to
The first and second memory cell pairs (MC11 and MC12), (MC21 and MC22), . . . , and (MCn1 and MCn2) may be connected to the same source line and the connected word lines may be electrically connected to each other so that the first and second memory cell pairs may always be selected together. Therefore, disturbances that may be generated between the first and second memory cells (MC11 and MC12), (MC21 and MC22), . . . , and (MCn1 and MCn2) may be prevented or reduced. According to an example embodiment and referring to first and second memory cell pairs (MC11 and MC12) and (MC21 and MC22), the drain of the second memory cell MC12 may be separated from that of the first memory cell MC21. The drains of the second memory cells and those of the first memory cells may be connected to the first bit lines BL11, BL21, . . . , and BLm1 and the second bit lines BL12, BL22, . . . , and BLm2, respectively. Therefore, disturbance that may be generated between neighboring memory cells connected to the same drain may be prevented by using separate drains according to an example embodiment. Although example embodiments are described with respect to the drain, this is descriptive, and either the source and/or the drain may be separated as dictated by the charge storing mechanism.
Methods of operating a semiconductor memory device according to example embodiments will now be described with reference to
As illustrated in
Methods of operating the semiconductor memory device illustrated in
Each of the plurality of sub-memory cell array blocks 12-1, 12-2, . . . may be configured the same as illustrated in
Methods of operating the semiconductor memory device illustrated in
The semiconductor memory device illustrated in
Example embodiments describe a memory cell in a memory cell array of a semiconductor memory device including a floating body transistor. According to example embodiments, a semiconductor memory device having a memory cell that conventionally does not have a capacitor (e.g., a memory cell employing a variable resistor as a data storage element or a flash memory) is also described.
According to an example embodiment, a region connected to a bit line of a second memory cell MC12 may be connected to a first bit line by overlapping the first bit line. A region connected to a bit line of a first memory cell MC21 may be connected to a second bit line by overlapping the second bit line. Thus, the regions that are connected to bit lines of the second and first memory cells MC12 and MC21 may be separated from each other. Further, the word and source lines that may be connected to the first and second memory cells MC11 and MC12 may be simultaneously activated. Consequently, a disturbance that may occur between memory cells may be prevented or reduced. Moreover, the memory cells may be disposed in a diagonal direction to enhance integration density of a semiconductor memory device.
According to an example embodiment in which word lines (or sub-word lines) may be connected to the first and second memory cells MC11 and MC12, and may be electrically connected to each other, the number of word lines driven by a row controller may be reduced and a layout area of the row controller may be reduced. The number of required sub-word line drivers may be reduced, facilitating the use of a sub-word line driver structure.
Accordingly, a semiconductor memory device and a method of arranging a memory cell array thereof are may prevent or reduce disturbance between adjacent memory cells, improve integration density of the semiconductor memory device, and employ a sub-word line structure.
While example embodiments have been particularly shown and described, it will be understood by one of ordinary skill in the art that variations in form and detail may be made therein without departing from the spirit and scope of the claims.
Claims
1. A semiconductor memory device comprising a memory cell array, the memory cell array comprising:
- a word line pair including a first word line and a second word line that are electrically connected to each other;
- a source line;
- a bit line pair including a first bit line and a second bit line;
- a first memory cell oblique to the first and second word lines, including a gate and first and second regions, the gate connected to the first word line, and the first and second regions respectively connected to the second bit line and the source line; and
- a second memory cell oblique to the first and second word lines, including a gate, a third region, and the second region, the gate connected to the second word line, the third region connected to the first bit line,
- wherein the first word line and the second word line are configured so that the first word line and the second word line may be simultaneously activated.
2. The semiconductor memory device of claim 1, wherein the word line pair are arranged in a first direction,
- the source line is arranged in the first direction between the first word line and the second word line,
- the bit line pair is arranged in a second direction perpendicular to the first direction, and
- the first and second memory cells are arranged in a third direction between the first and second directions.
3. The semiconductor memory device of claim 1, wherein the first region of the first memory cell overlaps the second bit line, and
- the third region of the second memory cell overlaps the first bit line.
4. The semiconductor memory device of claim 1, wherein the first memory cell includes a floating body transistor in which the first region is a drain region and the second region is a source region, and
- the second memory cell includes a floating body transistor in which the third region is a drain region and the second region is a source region.
5. The semiconductor memory device of claim 4, further comprising:
- a row controller configured to control the word line pair and the source line; and
- a column controller configured to control the bit line pair,
- wherein the memory cell array further comprises a sensing block including a current sense amplifier configured to amplify current flowing through the first bit line and the second bit line during a read operation.
6. The semiconductor memory device of claim 4, further comprising:
- a row controller configured to control the word line pair and the source line; and
- a column controller configured to control the bit line pair,
- wherein the memory cell array further comprises a voltage sense amplifier configured to amplify voltage of the first bit line and the second bit line during a read operation.
7. The semiconductor memory device of claim 4, further comprising:
- a main word line connected to the word line pair; and
- a main source line connected to the source line.
8. The semiconductor memory device of claim 7, further comprising:
- a row controller configured to control the main word line and the main source line; and
- a column controller configured to control the bit line pair,
- wherein the memory cell array further comprises a sensing block having a current sense amplifier configured to amplify current flowing through the first bit line and the second bit line during a read operation.
9. The semiconductor memory device of claim 7, further comprising:
- a row controller configured to control the main word line and the main source line; and
- a column controller configured to control the bit line pair,
- wherein the memory cell array further comprises a sensing block having a voltage sense amplifier configured to amplify voltage of the first bit line and the second bit line during a read operation.
10. The semiconductor memory device of claim 4, further comprising:
- a main word line;
- a main source line; and
- a plurality of word line selection signal lines,
- wherein the memory cell array further comprises, a plurality of sub-memory cell array blocks that include the first memory cell and the second memory cell,
- a plurality of word line selection signal drivers connected to the corresponding word line selection signal lines,
- a sub-word line driver connected to an output signal line of the corresponding one of the plurality of word line selection signal drivers and the main word line, and configured to drive the word line pair, and
- a sub-source line driver connected to an output signal line of the corresponding one of the plurality of word line selection signal drivers and the main source line, and configured to drive the source line.
11. The semiconductor memory device of claim 10, wherein the sub-word line driver and the sub-source line driver are alternately arranged with respect to each of the plurality of sub-memory cell array blocks.
12. The semiconductor memory device of claim 11, further comprising:
- a row controller configured to control the main word line, the main source line, and the plurality of word line selection signal lines; and
- a column controller configured to control the first bit line and the second bit line,
- wherein the memory cell array further comprises a sensing block including a current sense amplifier that amplifies current flowing through the first bit line and the second bit line during a read operation.
13. The semiconductor memory device of claim 11, further comprising:
- a row controller configured to control the main word line, the main source line, and the plurality of word line selection signal lines; and
- a column controller configured to control the bit line pair,
- wherein the memory cell array further comprises a sensing block including a voltage sense amplifier that amplifies voltage of the first bit line and the second bit line during a read operation.
14. The semiconductor memory device of claim 1, wherein the first memory cell includes a first access transistor in which the second region is a source region and a gate is connected to the first word line, and a first variable resistor is connected between a drain of the first access transistor and the first region, and
- the second memory cell includes a second access transistor in which the second region is a source region and a gate is connected to the second word line, and a second variable resistor is connected between a drain of the second access transistor and the third region.
15. The semiconductor memory device of 1, wherein the first memory cell includes a first selection transistor in which the second region is a source region and a gate is connected to the first word line, and a first memory transistor is connected between a drain of the first selection transistor and the first region, and
- the second memory cell includes a second selection transistor in which the second region is a source region and a gate is connected to the second word line, and a second memory transistor is connected between a drain of the second selection transistor and the third region.
16. The semiconductor memory device of claim 15, wherein each of the first and second memory transistors includes a Silicon-Oxide-Nitride-Oxide-Silicon (SONOS) cell.
17. A method of arranging a memory cell array of a semiconductor memory device, comprising:
- arranging a word line pair including a first word line and a second word line that are electrically connected to each other in a first direction;
- arranging a source line in the first direction between the first and second word lines;
- arranging a bit line pair including a first bit line and a second bit line in a second direction perpendicular to the first direction;
- arranging a first memory cell including a gate connected to the first word line, and first and second regions respectively connected to the second bit line and the source line, in a third direction between the first direction and the second direction; and
- arranging a second memory cell including a gate connected to the second word line, and a third region and the second region respectively for connecting to the first bit line and the source line, in the third direction.
18. The method of arranging a memory cell array of a semiconductor memory device of claim 17, wherein arranging the first memory cell includes arranging the first region to overlap the second bit line, and
- arranging the second memory cell includes arranging the third region to overlap the first bit line.
19. The method of arranging a memory cell array of a semiconductor memory device of claim 18, further comprising:
- arranging a main word line in the first direction; and
- arranging a main source line in the first direction,
- wherein arranging the main word line and the main source line includes respectively connecting the main word line and the main source line to the word line pair and the source line.
20. The method of arranging a memory cell array of a semiconductor memory device of claim 18, further comprising:
- arranging a main word line in the first direction;
- arranging a main source line in the first direction;
- arranging a plurality of word line selection signal lines in the first direction;
- arranging a plurality of sub-memory cell array blocks including the first memory cell and the second memory cell, and a plurality of word line selection signal drivers for connecting to the corresponding word line selection signal lines in the memory cell array; and
- alternately arranging a sub-word line driver, connected to an output signal line of the corresponding one of the plurality of word line selection signal drivers and the main word line and configured to drive the word line pair, and a sub-source line driver connected to an output signal line of the corresponding one of the plurality of word line selection signal drivers and the main source line and configured to drive the source line, with respect to each of the plurality of sub-memory cell array blocks.
21. The method of arranging a memory cell array of a semiconductor memory device of claim 18, wherein arranging the first and second memory cells further includes arranging the first memory cell including a floating body transistor in which the first region is a drain region and the second region is a source region, and
- arranging the second memory cell including a floating body transistor in which the third region is a drain region and the second region is a source region.
22. The method of arranging a memory cell array of a semiconductor memory device of claim 18, wherein arranging the first memory cell further includes arranging a first access transistor in which the second region is a source region and a first variable resistor, by connecting a gate of the first access transistor to the first word line and connecting the first variable resistor between a drain of the first access transistor and the first region, and
- arranging the second memory cell further includes a second access transistor in which the second region is a source region and a second variable resistor, by connecting a gate of the second access transistor to the second word line and connecting the second variable resistor between a drain of the second access transistor and the third region.
23. The method of arranging a memory cell array of a semiconductor memory device of claim 18 wherein arranging the first memory cell further includes connecting a first selection transistor so that the second region is a source region, connecting a gate of the first selection transistor to the first word line, and connecting a first memory transistor between a drain of the first selection transistor and the first region, and
- arranging the second memory cell further includes connecting a second selection transistor so that the second region is a source region, connecting a gate of the second selection transistor to the second word line, and connecting a second memory transistor between a drain of the second selection transistor and the third region.
24. The method of arranging a memory cell array of a semiconductor memory device of claim 23, wherein each of the first and second memory transistors includes a Silicon-Oxide-Nitride-Oxide-Silicon (SONOS) cell.
5332923 | July 26, 1994 | Takeuchi |
5442212 | August 15, 1995 | Eimori |
6403413 | June 11, 2002 | Hayano et al. |
6621725 | September 16, 2003 | Ohsawa |
6903961 | June 7, 2005 | Tsukikawa et al. |
7085156 | August 1, 2006 | Ferrant et al. |
7136301 | November 14, 2006 | Tokumitsu |
7177175 | February 13, 2007 | Fazan et al. |
7692957 | April 6, 2010 | Chang |
7745894 | June 29, 2010 | Asao et al. |
7781803 | August 24, 2010 | Nishimura et al. |
7795658 | September 14, 2010 | Shino |
7847332 | December 7, 2010 | Lee |
7961506 | June 14, 2011 | Liu |
20060091462 | May 4, 2006 | Okhonin et al. |
20060092739 | May 4, 2006 | Fujita et al. |
20060098481 | May 11, 2006 | Okhonin et al. |
20060126374 | June 15, 2006 | Waller et al. |
20060131650 | June 22, 2006 | Okhonin et al. |
20070023833 | February 1, 2007 | Okhonin et al. |
20070058427 | March 15, 2007 | Okhonin et al. |
20070064489 | March 22, 2007 | Bauser |
20070085140 | April 19, 2007 | Bassin |
20070097751 | May 3, 2007 | Popoff et al. |
20070138524 | June 21, 2007 | Kim et al. |
20070138530 | June 21, 2007 | Okhonin |
2006-156986 | June 2006 | JP |
2007-503678 | February 2007 | JP |
10-0675297 | January 2007 | KR |
- Hyun-Jin Cho et al. “A novel capacitor-less DRAM cell using Thin Capacitively-Coupled Thyristor (TCCT)”, IEDM 2005, T-RAM.
Type: Grant
Filed: May 15, 2009
Date of Patent: May 15, 2012
Patent Publication Number: 20090290402
Assignee: Samsung Electronics Co., Ltd. (Gyeonggi-do)
Inventors: Ki-Whan Song (Yongin-si), Yeong-Taek Lee (Seoul)
Primary Examiner: Tuan T Nguyen
Assistant Examiner: Lance Reidlinger
Attorney: Harness, Dickey & Pierce
Application Number: 12/453,595
International Classification: G11C 5/02 (20060101);